William w



(No Model.)

W. W. KING.

ELECTRIC ARC LAMP.

Patented Apr. 28, 1885.

VI an FIGJI- A UNITED. STATES PATENT OFFICE.

WILLIAM WV. KING, OF ST. LOUIS, MISSOURI, ASSIGNOR OF ONE-HALF TOVILLIAM SOMERVILLE, OF SAME PLACE.

ELECTRIC-ARC LAMP.

SPEGEFICATIQN forming part of Letters Patent No. 316,791, dated April28, 1885.

Application filed April 1, 1884. (No model.)

To all whom it may concern.-

Be it known that 1, WILLIAM W. KING, of the city of St. Louis and Stateof Missouri, have invented a certain new and useful Improvement inElectric-Arc Lights, of which the following is a full, clear, and exactdescription, reference being had to the accompanying drawings, formingpart of this specification.

My invention consists in the manner of con necting the dash-pots withthe mechanism by which the rack-rod of the upper carbon is sup ported,so as to check the downward motion of the carbon; also, in the describedconstruction of the rack-rod, which allows the upper carbon to drop intocontact with the lower carbon when it has descended a certain distance,as set forth.

Figure I is a vertical section of my device on line I I, Fig. II, thefront cylinder being shown in section and its piston and rod inelevation in position for attachment to its disk. Fig. II is ahorizontal section on the line II II, Fig. I.

A is a frame or case in which the supporting mechanism of the uppercarbon is contained.

r is the rack-rod, to whose lower end the upper carbon is connected, asusual. The rack r of this rod engages with a spur-wheel, Z), by whichthe rod is supported. At the side of the spur-wheel is a ratchet-wheel,c, that is fast upon the shaft 9, upon which the spur-wheel is loose.

b is a dog upon the side of the spur'wheel, that engages with theratchet-wheel c, the arrangement being such as to prevent the spurwheelturning on the shaft in a direction to allow the descent of therack-rod, while the spur-wheel is capable of turning in the oppositedirection on the shaft, so that the rackrod may be pushed upward at anytime without rotating the shaft The dog is held to the ratchet-wheel bya spring, I)". The shaft 9 has bearing on an arm, 2, hinged to the caseor frame A at one end, i, and at the other end hinged to the core a ofthe solenoids s s. The upper solenoid is in the main line or circuit andthe lower solenoid in the shunt line or circuit, as shown.

Upon the shaft 9 are two disks, (1 d, the former having a notchedperiphery that is engaged by an adjustable dog, J, that prevents theturning of the shaft 9 when in its normal position. XVhen, however, thedistance between the carbons becomes so great that the resistancethrough the upper solenoid and carbons and consequent increased currentthrough the lower helix causes the core a to descend, the disk (I isdrawn out of engagement with the dogf, and the rack-rod r descends,turning the shaft g. As the point of the upper carbon approaches thelower carbon the resistance through the upper helix decreases and theelectric current increases, raising the core a and engaging the disk orwheel (1 with the dog f, thus preventing the further descent of therack-rod and carbon.

I claim no novelty in the above-described mechanism.

7t 7c are wrist-pins upon the outer sides of the disks (1 and d.

Zlare the rods of pistons m of oscillating cylinders e, formingdash-pots. The purpose is to check the rotation of the shaft 9 when thedisk (Z is freed from engagement with the dog f.

To give a uniform and easy movement to the shaft 9 and rod 1' in thedescent of the latter, I set the pins It at an angle of ninety degreesto each other, so that one piston shall be at halfstroke when the otheris at a dead-center. .The dash-pot cylinders are hinged to the frame orcase A at 6, so as to accommodate themselves to the positions of thepistons. The cylinders may contain glycerine or other liquid to clog themovement of the pistons. The upper end, h, of the rack-rod r is devoidof teeth, so that when the rod has descended to a certain position itshall descend without hinderance,bringing the two carbons into contact,and thus allowing the electric current to pass and avoiding the breakingof the circuit and consequent putting out of other lights that may be inthe same circuit.

I have found that unless the dash-pots are at right angles it isimpossible to get an even downward motion of the dash-pots. If thedash-pots are connected to the shaft at any other angle than ninetydegrees, the downward motion of the rod will not be uniform. In an arclamp the steadiness of the light cannot be maintained except by the niceadjustment of the distance of the carbon points from each other, andconsequently the checking influence of the dash-pots should becontinuously uniform. My manner of connecting the dash-pots has thisadvantage of the even retarding of the feeding of the carbon.

The toothed portion of my rack-bar above the axial line of thesupporting-pinion being of slightly less length than the uneonsumedcarbon beneath its ferrule, the rack-bar will be certain to drop downout of engagement with the pinion before the upper carbon is quiteconsumed.

I am aware that it is old to employ two or more dash-pots, which areconnected to the same pin to retard the mechanism controlling thedownward movement of the carrier-rod.

I am also aware that it is old to reduce the diameter of the carrier-rodto permit it to drop and slip past its support before the upper carbonis quite consumed. Such devices for re tarding and dropping thecarrier-rod I do not therefore claim, broadly.

I claim as my invention 1. The combination with a carbon-carrier, of ashaft geared thereto so as to be rotated by the movement of the saidcarrier, and two oscillating dash-pots with reciprocating pistonspivoted to two crank arms on the said shaft, respectively, the two armsbeing substantially at an angle of ninety degrees to each other.

2. In an arc lamp, the combination, with the operatingpinion, of anupper rack-bar having the toothed portion above the axial line of thesupporting-pinion of slightly less length than the unconsumed carbonextends beyond the ferrule.

W'ILLIAM XV. KING.

Witnesses:

SAML. KNIGHT, Gno. H. KNIGHT.

